Process for printing and pad dyeing polyamide fibrous materials

ABSTRACT

Process for preparing on textile materials consisting of polyamide fibres or of their mixtures with cellulose fibres, or containing such fibres or fibre blends, prints and pad-dyeings having extremely good fastnesses to wet processing, using reactive dyestuffs for printing and padding, and fixing these dyestuffs by steaming at a pH range of from about 6 to 11, preferably of from 7 to 8.5.

Pelster et al.

United States Patent [191 221 Filed: June is, 1972 211 Appl. No; 263,157

Related US. Application Data [63] Continuation of Ser. No. 23,473, March 27,1970,

abandoned.

[30] Foreign Application Priority Data Apr.,1, 1969 Germany 1916627 [52] US. Cl. 8/54, 8/1 E, 8/21 B,

[51] Int. Cl D06p l/38 [581' Field of Search'.........'8/178, 163, 1 E, 54, 21 B [451 June 11, 1974 [56] References Cited UNITED STATES PATENTS 3,042,477 7/1962 Hadfield et a1, 8/163 X 3,097,043 7/1963 Mills 8/163 3,660,393 5/1972 Ackermann et a1. 8/163 X 3,663,156 5/1972 Meiningcr et a1 8/163 X 3,697,500 10/1972 Ackermann et al. 8/163 X OTHER PUBLICATIONS H. U. Schmidlin, Preparation and Dyeing of Synthetic Fibers, 1963, pp. 218 and391, Publ. Chapman & Hall Ltd., London.

Primary ExaminerThomas .1. Herbert, Jr. Attorney, Agent, or FirmCurtis, Morris & Safford [5 7] ABSTRACT Process for preparing on textile materials consisting of polyamide fibres or of their mixtures with cellulose fibres, or containing such fibres or fibre blends, prints and pad-dyeings having extremely good fastnesses to wet processing, using reactive dyestuffs for printing and padding, and fixing these dyestuffs by steaming at a pH range of from about 6 to 11, preferably of from 7 to 8.5.

3 Claims, No Drawings PROCESS FOR PRINTING AND PAD DYEING POLYAMIDE FIBROUS MATERIALS This application is a continuation application of US. Pat. application Ser. No. 23,473, filed Mar. 27, 1970,

now abandoned.

dyes, disperse and pigment dyestuffs. The fastness hitherto required for goods made of polyamides are more or less attained by these dyestuff types. For improving the fastnesses to wet processing, however, special operations using suitable auxiliary agents are necessary which cause detrimental hardening of the polyamide goods, as well as an undesired extension of the process and make it highly expensive. Further, in the rinsing and washing operations, especially acid dye-stuffs tend easily to staining white spots where the polyamide goods have not been printed.

lt is also known that polyamide fibrous materials can be dyed by means of reactive dyestuffs under the same fixing conditions as those for acid dyestuffs, but the resulting dyeingsshow only moderate fastnesses to wet processing.

Articles made from polyamide fibrous materials to be employed for bedding and table-linen, however, have to meet far higher requirements as to fastnesses. Until now, woven and knitted fabrics made from polyamide fibrous materials have generally been washed at a temperature of 40 C, at most of 60C, whereas these articles, nowadays, should be washable at boiling temperatures and, correspondingly, the prints and dyeings should resist to frequent household washings at about 95 C in a washing machine.

Thus, the hitherto existing printing and dyeing processes for polyamide goods can no longer be applied to these polyamide articles which have to be fast to boiling, due to the insufficient fastness to washing of the cited dyestuff types. For this reason, a process producing prints and dyeings on polyamide fibres having very high fastnesses to wet processing would mean a considerable advance.

It has now been found that it is possible to obtain on textile materials consisting of polyamide fibres or of their mixtures with cellulose fibres, or containing such fibres of fibre blends, prints and pad-dyeings of high fastnesses to wet processing by using reactive dyestuffs for printing and padding, and fixing these dyestuffs by steaming at a pH range of from about 6 to 11, preferably of from 7 to 8.5.

As reactive dyestuffs, all organic dyestufis of this category can be used in the process of the invention, i.e., such dyestuffs having at least one reactive group, a precursor for such a group or a reactive substituent, which react in known manner with the hydroxy groups of cellulose materials, thus forming a covalent bond. Suitable parent components of these organic dyestuffs are especially those of the series of anthraquinone, azo and phthalocyanine dyestuffs; both the latter may contain metal or not. Examples of reactive groups and precursors thereof are the radicals of the formulae x-Ycn,-cri,z

in which X represents a covalent bond or the group R being a hydrogen atom or an optionally substituted alkyl group, Y represents a -SO or -CO- group and Z a hydroxy group or the radical of a monoor polybasic acid, such as a halogen atom, above all chlorine, a sulfuric acid, thiosulfuric acid or phosphoric acid radical, or an amino group substituted by alkyl or aryl radicals, or a quaternary ammonium group. Further, those reactive groups may be used, the formulae of which are in analogy to the above mentioned formulae, in which, however, the sequence of the radicals -X- and -Y- has been changed. Examples of groups of said type are the vinylsulfonyl, vinylsulfonylamino, B-sulfatoethylsulfonyl, ,B-thiosulfato-ethylsulfonyl, B-sulfatoethylsulfonamido' and the B-sulfato-ethylcarbonamido group.

Reactive substituents in reactive dyestuffs are those which can be easily splitoff and then leave an electrophilic radical. Examples of such substituents are halogen atoms attached to the following ring systems: quinoxaline, triazine, pyrimidine, phthalazine and pyridazone, inparticular the monochlorotriazine, dichlorotriazine, trichloro-pyrimidine, dichloro-quinoxaline and the dichloro-phthalazine groups.

Finally, it is also possible to use reactive dyestuffs having one or more 2,2,3,3-tetrafluoro-cyclobutane-lacroylamino groups or a radical formed by condensation of 2-N-methylamino-5-hydroxynaphthalene-7- sulfonic acid with 2,4-dichloro-6-methoxy-1,3,5- triazine.

Examples of reactive dyestuffs of the kind cited above are described in U.S. Pat. Nos. 2,670,265; 2,657,205; 3,197,456; 3,349,097; 3,324,151; 3,261,823; 3,417,074; 3,278,549; 3,360,524; 3,278,516; 3,360,509 and 3,360,505 as well as in French Pat. No. 1,448,660.

According to the process of the invention printing is effected using neutral printing pastes to which a product capable of splitting off alkali is added'or an alkaline salt of from weak to medium strong acids, for example sodium acetate, the sodium salt of trichloro-acetic acid, sodium carbonate, sodium bicarbonate or trisodium phosphate, or else to which small amounts of alkalis are added. The same goes for the pad-steam dyeing process, in that case the polyamide material is impregnated on a foulard using a slightlythickened dye bath con taining besides the dyestuff also the same abovementioned auxiliary agents, and subsequently the textiles are steamed.

The printing thickeners or combinations of thickeners employed have to meet the general requirements called for in the printing of synthetic fibres as to tinctorial power, sharpness of the outlines, capability of being washed out and effect relative to the feel. The thick ener should have no reducing effect, it should be neutral or adjusted to neutral.

The new process can be explained using the example of vinylsulfone dyestuffs. The small quantities-of alkali in the printing pastes or padding liquors are necessary for converting that dyestuff being present in the form of the sulfato-ethylsulfone compound into the reactive vinylsulfone form, in which it forms a covalent bond while reacting with the terminal Nl-l groups of the polyamide, thus imparting the prints and dyeings produced remarkably good fa'stnesses to wet processing not attained on polyamide material until now.

1. alkali F-S OrCHrCHz--OS 03N8 F-S Oz-CH CH:

processing, for in this lower pH range no reaction between the dyestuff and the fibre occurs.

in the process of the invention such dyestuffs are advantageously used of which the strength of their saltlike bond to the polyamide material being relatively weak, so that the portion of not covalent fixed dyestuff is easilyremovable by washing out. Dyestuffs of this kind are those having at least one, preferably two and more, water-solubilizing groups, such as carboxylic acid and/or sulfonic acid groups.

I in some cases, especially if complex metal dyestuffs are applied or dyestuffs containing a number of watersolubilizing groups which is too small in comparison to their molecular sizes, the dyestuff portion not being linked by a covalent bond, i.e., in a salt-like manner only, is absorbed onto the fibre more powerfully,'t'hus faster to washing. This portion of the dye, however, remains on the fibre occasionally in the washing operation under mild conditionsdisclosed before so that, thereupon, the results of a later, more severe washing test would be correspondingly poorer.

But in this event, an after-treatment of the prints or pad-dyeings obtained by using the foregoingmentioned dye-stufis with an aqueous weakly alkaline solution, preferably with dilute ammonia, will quantitatively remove the excess dyestuff likewise. The remaining reactively bound dyestuff then shows very good fastnesses to .wet processing.

According to the printing and pad-dyeing process of the invention, the cellulose .fibre portion of the fibre mixtures with 'polymide fibres may be of native or regenerated origin.

Fixing of the prints and pad-dyeings is carried out by steaming at temperatures ranging between 98 and 130 C. In order to get a uniform and optimum dyestuff fixation, steaming periods are necessary which are generally between 10 and 30 minutes. The color yield is improved by steaming under elevated pressures (up to 1.5 atmospheres gauge). The polyamide material can be treated either in discontinuously operating steamers, for example in a star steamer, or in continuously operating steamers, such as Krostewitz, Mather-Platt or suspension-loop steamers etc. But continuous steamers cannot be operated under atmospheric excess pressure, and therefore the color yield on polyamide fibres, obtained by using this equipment, is correspondingly lower.

This disadvantage can be eliminated according to the process of the invention by a pre-treatment of the polyamide material, before its printing or dyeing, with water or steam at elevated temperatures of up to about C and under atmospheric excess pressure (of up to 1.5 atmospheres gauge), which treatment results in a certain swelling of the fibre, especially in a partial splitting of the -NH-CO-chains of the polyamide with the simultaneous formation of new terminal amino groups suitable for binding the dyestuffs. Consequently, in the case of polyamide material pre-treated in the above manner it is possible, after the printing or dyeing operation, to-steam the goods continuously at a temperature of about 102 C without an excess pres sure and to obtain a substantially higher color yield than on goods which are not pre-treated. A discontinuous pressure steam treatment of the printed or padded polyamide goods thus is unnecessary, because it does not lead to further substantial increase in color yield.

According to the simplest way, the pre-treatment is carried out in one operation along with the usual prewashing or hydrofixing of the goods, at a pressure of from 0.5 to 1.5 atmospheres gauge, and at a tempera-- ture between 108 and l30 C in a neutral or, preferably, weakly alkaline medium; a greater number of terminal amino groups being formed in this weakly alkaline medium. The polyamide material may also be pretreated by steaming in a star steamer at a pressure of from 0.5 to 1.5 atmospheres gauge without or, preferably, after having been impregnated using small amounts of alkali or of products capable of splitting off alkali (for example a solution of 10 g of sodium acetate per litre of water).

At the final rinsing and washing process after the printing and steaming of the goods, the technical progress of the process of the invention resides in the fact that washing and rinsing can be carried out in a neutral or weakly alkaline medium, at which dyestuff that is fixed merely like an acid dyestuff not only has no dyeing effect, but is completely stripped from the textile material. Under the same conditions normal acid dyestuffs wouldshow very heavy bleeding effects. Just so, the separate process for improving the fastness to wet processing, otherwise usual up to now, is no longer necessary.

The following Examples illustrate the invention; parts and percentages being by. weight unless otherwise stated.

EXAMPLE 1 50 g of the dyestuff of the formula SOaH are dissolved in 250 g ofboiling water. The solution is stirred into 500 g of an aqueous thickener of 9 percent strength comprising an ether of locust bean flour. Subsequently, g of the sodium salt of trichloro-acetic acid, dissolved in water at a ratio of 1:1, and finally, 185 g of cold water are added to the paste.

A fabric made of polyamide-6 fibres is printed by means of the above printing paste, then dried and subsequently steamed for 30 minutes in a star steamer at about 1 12 C and at0.5 atmosphere gauge. Finally, the goods are rinsed and washed with cold and warm water and then soaped in an aqueous bath at about 80 C, with addition of an anion-active detergent.

A yellow print having good fastness to wet processing is obtained.

EXAMPLE 2 50 g of the dyestuff of the formula 0H OCH: 7 N=a g V sol-when,

are dissolved in 250 g of boiling water and stirred into 500 g of an aqueous thickener of 9 percent strength comprising an ether of locust bean flour. Subsequently, 15 g of sodium acetate, dissolved in water at a ratio of 1:1, and 185 g of cold water are added to the paste.

A knitted fabric made of polyamide-6.6 fibres is printed by means of the above printing paste and subsequently dried. The fabric is then steamed for minutes in a star steamer at 1.5 atmospheres gauge and about l26128 C.

Finally, the goods are rinsed in cold and warm water and soaped in an aqueous bath at about 80 C, while adding a detergent. A redprint having good fastnesses is obtained.

EXAMPLE 3 50 g of the dyestuff of the formula OS3N8 are dissolved in 250 g of boiling water. The solution is stirred into 500 g of an aqueous thickener of 9 percent strength comprising an ether of locust bean flour. Subsequently, 5 g ofdisodium phosphate and 195 g of cold,

' water are added to the paste.

A fabric made of polyamide fibres is printed by means of the above paste and then dried. Subsequently, the goods are steamed continuously in a suspension loop steamer for 30. minutes at about lO2l04 C. Rinsing of the fabric in cold and hot water is effected with the addition of l to 1.5 cc of a percent ammonia, per litre of liquor. Then the goods are soaped in an aqueous bath while adding the same amount of ammonia and together with a detergent, at temperatures between 60 and 80 C.

A brilliant, deep blue print having good fastness properties is obtained.

EXAMPLE 4 100 g of the dyestuff of the formula NQ-SOrCEn-OHT-O-s 0311 are dissolved in 300 g of boiling water. The solution is stirred into 500 g of a thickener, consisting of a mixture of equal parts of a 25 percent aqueous thickening of crystal gum and of a 10 percent aqueous thickening of a vegetable flour derivative. Subsequently, 20 g of sodium acetate, dissolved in water at a ratio of 1:1, 10 g of the sodium salt of m-nitrobenzenesulfonic acid as oxydation agent, as well as 70 g of cold water are added to the paste.

A fabric consisting of a mixture of 60 percent polyamide fibres and 40 percent of cellulose fibres is printed by means of the above printing paste and then dried. Steaming of the goods is effected for 20 minutes in a star steamer at 0.5 atmospheres gauge and about 112 C.,

Finally, the goods are rinsed in cold and warm water and soaped in an aqueous bath at about 80 C, with addition of a non-ionic detergent.

A black print having good fastness properties is obtained.

EXAMPLE 5 g of the dyestuff of the formula are dissolved in 250 g of boiling water. into this solution 150 g of a 10 percent aqueous solution of sodium alginate are added. Subsequently, 10 g of Cl C- COONa, dissolved in water at a ratio of 1:1 and 540 g V of cold water are added.

EXAMPLE 6 50 g of 'the dyestuff of the formula S O3Na. OH

OaND JNH-XENIQ spheric excess pressure of 1.5 atmospheres gauge and at 128 C, at a pH of 8 using an aqueous medium with addition of Cl-l COONa, is printed by means of the above printing paste and then dried. Subsequently, the

goods are'steamed for 20 to 30 minutes in a continuous steamer at about 102 C without the application of atmospheric excess pressure. Finally, the material is rinsed with cold and warm water and soaped in an aqueous bath at about 80 C while a detergent is added.

A scarlet red printhaving good fastness properties is obtained.

, EXAMPLE 7 50 g of the dyestuff of the formula SOaNa OH are mixed with 50 g of urea and dissolved in 250 g of boiling water. The solution is stirred into 500 g of an aqueous thickener of 10 percent strength comprising an ether of locust bean flour. Further, there are added .to the paste 10 g of cl-l COONa and 140 g ofcold water.

A fabric made of polyamide fibres, pre-treated with steam'in a star steamer at an excess pressure of 1.5 atmospheres gauge and a temperature of 128 C, is printed by means of the above printing paste and then dried. Then the goods are steamed and finished according to Example 6.

'An orange print having good fastness properties is are dissolved in 250 g of boiling water. This solution is stirred into 500 g of an aqueous thickener of 10 percent strength comprising an ether .of locust bean flour. Thereupon, 5 g of Na l-l P and 195 g of cold water are added to the paste.

A fabric consisting of a mixture of 80 percent of polyamide fibres and 20 percent of cotton fibres, impregnated with a 1 percent aqueous solution of sodium acetate and pre-steamed in a star steamer at 1.5 atmo spheres gauge and 128 C, is printed by means of the above printing paste and then dried. Steaming and finishing of the goods are effected as in Example A red print of good color intensity and good fastness properties is obtained.

EXAMPLE 9 50 g of the dyestuff of the formula FzC--GF2 SIOaNa OH NH-C OCH=CHJJH Hz CH3 SO Na 03N8 are dissolved in 250 g of boiling water and stirred into 500g of an aqueous, thickener of 10 percent strength comprising a vegetable flour. Subsequently, g of,

' CH COONa and 185 g of cold water are added to the paste.

A fabric made of polyamide fibres, pre-steamed in a high temperature equipment at 0.5 to- 1.5 atmospheres gauge and 108 to C, is printed by means of the above printing paste and then dried. Subsequently, the fabric is steamed and finished according to Example 6.

A deep red print having good fastness properties is obtained.

EXAMPLE 10' 50 g of the dyestuff of the formula are mixed with 50 g of urea, dissolved in 250 g of boiling water and then stirred into 500 g of an aqueous thickener of 10 percent strength'comprising a vegetable flour. Finally, 10 g of CHQCOONa and'l40 g of cold water are added to the paste.

. A fabric made of polyamide fibres, pre-treated according to Example 6, is printed by means of the above printing paste and then dried. Subsequently, the material is steamed and washed as in Example 6.

A red print having good fastness properties is obtained. I

EXAMPLE 1] 50 g of the dyestuff of the formula are mixed with 50 g of urea and dissolved in 250 g of boiling water. The solution is stirredinto 500 g of an aqueous thickener of 10 percent strength comprising an ether of locust bean flour, then 15 g of CCI COONa, dissolved in water at a ratio of 1:1, as well as g of cold water are added to the paste.

A fabric made of polyamide fibres, pre-treated as in a P 6, s P i te by "55 1 9? tbsabqy Pri in EXAMPLE 12 50 g of the dyestuff of the formula I NH-OO-CHz-CHr-W son:

are mixed with 50 g of urea and dissolved in 250 g of boiling water. The solution is stirred into 500 g of an aqueous thickener of 10 percent strength comprising an ether of a vegetable flour. Finally, 10 g of CPL-,COOHa and 140 g of cold water are added to this aste. p A knitted article made from polyamide fibres, pretreated as in Example 6, is printed by means of the above printing paste and then dried. Thereupon, the goods are steamed continuously for 30 minutes at about 103 C without the application of atmospheric excess pressure. Subsequently, they are rinsed in cold and warm water and soaped in an aqueous bath at about 80 C while a detergent is added.

A red print having good fastness properties is obtained.

We claim: I. A process for preparing a print or pad-dyeing having good fastness to wet processing on a textile material are dissolved in 250 g of boiling water and stirred into containing polyamide fibers which comprises. applying 500 g of an aqueous thickener of 10 percent strength comprising an ether of a vegetable flour. Subsequently, 10 g of CH COONa and 190 g of cold water are added to the paste.

This printing paste is applied as in Example 6.

A yellow print having good fastnesses is obtained.

EXAMPLE 1 3 to said material a printing paste or a padding liquor containing a water-soluble reactive dyestuff, containing a compound capable of splitting off alkali or a sodium or potassium salt of a weak to medium strong acid and having a pH of from about neutral to about 8.5; and fixing said reactive, dyestuff on the fibers by steaming.

2. A process according to claim 1 wherein said fixing is by steam at a temperature of about 98 C. to about C. at a pressure of about atmospheric to about 1.5 atmospheres gauge.

3. A process according to claim 1 which further comprises washing said textile material subsequent to said fixing in a weakly alkaline aqueous bath. 

2. A process according to claim 1 wherein said fixing is by steam at a temperature of about 98* C. to about 130* C. at a pressure of about atmospheric to about 1.5 atmospheres gauge.
 3. A process according to claim 1 which further comprises washing said textile material subsequent to said fixing in a weakly alkaline aqueous bath. 